Plate For Heat Exchanger And Heat Exchanger Equipped With Such Plates

ABSTRACT

The invention relates to a plate intended to enable an exchange of heat between a first and a second fluid circulating in contact with the plate, said plate being configured to define a circuit for the first fluid. According to the invention, said plate comprises one or a plurality of protuberances intended to penetrate into a plate for collecting the first fluid and defining an inlet into and/or an outlet from the circuit. The invention also relates to an array of such plates and to a heat exchanger comprising such an array.

The invention relates to plates for heat exchangers and to plate heatexchangers, in particular for motor vehicles.

Exchangers, known as charge air coolers, permitting an exchange of heatbetween charge air, intended to supply the engine of the vehicle, and acoolant liquid are familiar in this field. They comprise a heat exchangearray including a stack of plates determining between them alternatecirculation channels for the charge air and for the coolant liquid.

Each plate guides the coolant liquid in a circuit comprising a pluralityof passageways. These plates exhibit the general shape of an elongatedrectangle having two large sides and small sides, each plate includingtwo bosses, a first boss exhibiting an inlet into the circuit for thecirculation of the coolant liquid and the other boss exhibiting anoutlet from the circuit for the circulation of the coolant liquid. Thebosses are situated along one and the same small side of the plate. Theyare intended to come into contact with the bosses of an adjacent platein order to permit the coolant liquid to pass from one circulationchannel to another. The coolant fluid is thus distributed between theplates via the inlet bosses. It then flows along passageways in thecircuits for the circulation of coolant liquid before exiting from saidplates at the level of the outlet bosses.

The charge air enters into the array at the level of one of the largesides of each plate before exiting therefrom at the level of the otherof the large sides. Each plate thus comprises a zone for the exchange ofheat between the coolant liquid and the charge air situated at the levelof the passageways and an inlet/outlet zone permitting the coolantliquid to enter into and to exit from each plate.

One disadvantage derives from the fact that the zone inside which thebosses are situated concentrates mechanical stresses capable of causingrupture of the elements that are brazed to one another. Anotherdisadvantage derives from the fact that this zone is highly prejudicialto the thermal performance because the charge air passing through thiszone, in particular between the bosses and the first longitudinalextremity of the plate, does not pass through the exchange zone betweenthe two fluids and accordingly exchanges no heat or almost no heat withthe coolant liquid.

A well-known approach to circumventing this problem is to modify thecomponent parts of the exchanger or to add a supplementary partconstituting a screen and permitting the passage through this zone ofthe fluid to be cooled to be limited. This has the effect ofcomplicating the component parts and/or the process of manufacturing ofthe exchanger, however, which can give rise to additional costs and,possibly, to an increase in the weight of the exchanger.

The object of the invention is to improve the situation.

To this end, it proposes a plate intended to permit an exchange of heatbetween a first and a second fluid circulating in contact with theplate, said plate being configured so as to define a circuit for thefirst fluid.

According to the invention, said plate comprises one or a plurality ofprotuberances intended to penetrate into a collector plate for the firstfluid and defining an inlet into and/or an outlet from the circuit.

The zone of each plate for the exchange of heat between the two fluidsis increased in size in this way, and the zone of each plate which doesnot participate in the exchange of heat is reduced in size. In fact, theonly part of a plate that does not participate directly in the exchangeof heat is situated at the level of the protuberances. It can also beappreciated that the protuberances, by being oriented in a differentway, are subjected to fewer stresses than the inlet/outlet zones for thefirst fluid, comprising bosses, of the known plates.

According to one aspect of the invention, said plate comprises twoprotuberances. For example, the plate comprises one inlet protuberance,through which the first fluid is able to enter, and one outletprotuberance, through which the first fluid is intended to exit.

According to another aspect of the invention, said plate comprises twosmall sides and two large sides, such that said plate possesses theshape of a rectangle, the one or a plurality of said protuberances beingsituated at the level of the small sides of the rectangle.

According to one illustrative embodiment, said plate and saidprotuberances comprise a bottom and margins defining said circuit, saidbottom of the one or a plurality of said protuberances and said bottomof said plate extending in one and the same plane. The bottom of the oneor a plurality of protuberances possesses, for example, one distalextremity lacking margins such that the first fluid is able to enterinto and/or to exit from the circuit via the distal extremity of theprotuberances.

According to another illustrative embodiment, the margins delimiting thecircuit are parallel to one other at the level of the one or a pluralityof protuberances and are flared out in the direction of the rest of thecircuit. They can continue to be parallel to one other as far as a zonein which a change takes place in the direction of flow of the firstfluid. The margins thus take the form of a funnel in proximity to theprotuberances. The expression proximity is used here to denote a zonesituated between 0 and 30 mm from the protuberance.

The invention also relates to an array for the exchange of heatcomprising a stack of plates of the kind described previously, saidplates being arranged in pairs such that two plates of the same pairdetermine between them a circulation channel for the first fluid.Similarly, two plates arranged opposite one another and belonging to twopairs of adjacent plates determine between them a circulation channelfor the second fluid.

The invention also relates to a heat exchanger comprising an array forthe exchange of heat as described previously and said collector plate,intended to be passed through by said protuberances of said plates.

According to one aspect of the invention, said exchanger comprises ahousing provided with four walls and in the interior of which housingsaid array is present, one of the four walls being said collector plate.The collector plate is a lateral wall of the housing, for example, thatis to say a plate situated opposite a peripheral lateral edge of theplates provided with the protuberances.

According to a further aspect of the invention, said heat exchangercomprises at least one inlet collector, into the interior of which theprotuberances of said plates defining the inlet of said circuitsdischarge, and one outlet collector, into the interior of which theprotuberances of said plates defining the outlet from said circuitsdischarge. In this way, the one or a plurality of inlet and/or outletcollectors is present on the exterior of the housing, that is to say onthe exterior of the array, such that the array in its entiretyparticipates in the exchange of heat between the two fluids.

According to one illustrative embodiment, the collector plate comprisesa plane section and collars surrounding said protuberances. The collarsparticipate in the mechanical support of the plates in relation to thehousing and conform to the contour of the protuberances in such a waythat the two fluids are separated in an impermeable manner.

According to one aspect of the invention, the margins of theprotuberances are terminated as a flat surface permitting the brazing ofthe protuberances to one another and extending in a plane parallel tothe plane in which the bottom of the protuberances extends. Two platesforming a pair of plates are in contact at the level of an internalsurface of the flat surfaces. The collars conform to an external surfaceof the margins of the protuberances and to an external surface of thebottom of the protuberances, a lateral surface of the flat surfaces thenhaving the ability to come into contact with the plane section of thecollector plate. Each collar surrounding the protuberances of one pairof plate thus comprises an upper part and a lower part, the lower partof the collar being in contact with the protuberance of a lower plate ofthe pair of plate, and the upper part of the collar being in contactwith the protuberance of an upper plate of the pair. The lower part andthe upper part of each collar are not in contact with one another.

According to one aspect of the invention, baffles are arranged insidethe exchanger, said baffles extending between two pairs of plates untilthey are in proximity to said collector plate. In this way, the bafflesdisrupt the flow of the second fluid circulating between the pairs ofplates from one lateral wall of the housing to the other. The expressionproximity is used here to denote a distance between 0 and 1 mm.

The invention also relates to a module for the admission of aircomprising an exchanger of the kind described previously.

Other characterizing features and advantages of the invention willbecome even more evident from a perusal of the following description ofillustrative embodiments provided by way of example with reference tothe accompanying figures. In these figures:

FIG. 1 is a view in perspective illustrating partially a heat exchangercomprising plates according to the invention;

FIG. 2 is a view from above of a plate of the exchanger in FIG. 1;

FIG. 3 is a partial view in perspective of a collector plate that ispassed through at the level of collars by the protuberances of theplates of the exchanger, and

FIG. 4 is a partial view illustrating the side of the exchangerexhibiting the collector plate.

As illustrated in FIG. 1, the invention relates to a heat exchanger 1permitting an exchange of heat between a first fluid, for example acoolant liquid C, and a second fluid, in particular a fluid to be cooledG. It can be a charge air cooler, inside which the fluid to be cooled isa flow of compressed air intended to supply an internal combustionengine, for example an engine of a motor vehicle. This flow ofcompressed air is cooled by the coolant liquid, in particular in theform of a mixture of water and glycol.

Said exchanger 1 comprises an array 2 for the exchange of heatcomprising a stack of plates 4 determining between them alternatecircuits 6, 8 for the coolant liquid C and for the fluid to be cooled G.The array 2 in this case is of generally parallepipedal shape andexhibits an inlet surface 10 and an opposing outlet surface, althoughnot depicted here, for the second fluid G. The plates 4 in this case arearranged in pairs in such a way that two plates 4 of one and the samepair determine between them a circulation channel for the coolant liquidC. The circuits 6 for the circulation of the fluid to be cooled G areprovided between two plates 4 arranged opposite two pairs of adjacentplates.

The exchanger can also comprise a housing 5, inside which the array 2 issituated. In this case, it comprises a left-hand lateral wall 18situated to the left in FIG. 1 and a right-hand lateral wall 19 situatedto the right in FIG. 1. The left-hand lateral wall 18 comes into contactwith left-hand lateral edges (reference 16 in FIG. 2) of the plates 4,whereas the right-hand lateral wall 19 comes into contact withright-hand lateral edges (reference 17 in FIG. 2) of the plates 4. Thehousing 5 likewise comprises an upper wall (not illustrated here) and alower wall 22 linking together the lateral walls 18, 19. The housing 5guides the fluid to be cooled G between the plates 4, from the inletsurface 10 as far as the outlet surface of the array 2.

The exchanger 1 may also comprise secondary exchange surfaces arrangedinside the circuits 6 for the circulation of the second fluid. Thesecondary exchange surfaces extend between two plates 4 arrangedopposite one another belonging to two pairs of adjacent plates. Thesecondary exchange surfaces in this case comprise corrugated baffles 52inserted between the plates inside the circuits 6 for the circulation ofthe fluid to be cooled.

FIG. 2 depicts a plate 4 according to the invention. Such a plate 4includes a bottom 31, for example, which is substantially plane,surrounded by a peripheral margin 32 terminated by a flat surface 34,permitting the brazing of the plates to one another. The circuit 8 forthe coolant liquid is defined, on the one hand, by said peripheralmargin 32 and, on the other hand, by one or a plurality of centralmargins 60, for example, arising from the material of the bottom 31 ofthe plate. The plates 4 possess the general shape of an elongatedrectangle, for example, having two large sides and two small sidescorresponding to the lateral edges 16, 17.

According to the invention, each plate includes two protuberances 38, 39intended to penetrate into a collector plate for the coolant liquid(corresponding to the left-hand lateral wall 18 in FIG. 1) and definingan inlet 40 into and/or an outlet 42 from the circuit 8. In this case,an inlet protuberance 38 of said protuberances exhibits the inlet 40,and an outlet protuberance 39 exhibits the outlet 42.

The protuberances 38, 39 are situated on the small sides 16, 17 of theplate, in this case at the level of the small side 16 situated on theleft in FIG. 2. They comprise a bottom 43 and margins 44 respectivelyextending the bottom 31 and the margins 32 of the plate 4 towards theexterior of the latter, that is to say beyond its lateral edge 16. Theprotuberances 38, 39 thus project in relation to the bottom 31 of theplate 4. The bottom 43 of the protuberances 38, 39 extends, for example,in the plane in which the bottom 31 of the plate 4 extends. Theprotuberances 38, 39 possess one distal extremity 45 lacking margins andtwo lateral extremities provided with margins 44. The coolant liquid isthus able to penetrate into or exit from the plate 4 via the distalextremity 45 of the protuberances 38, 39 and to be guided inside thecircuit 8 of the plate 4 via the base 31, 42 and the margins 32, 60, 44of the protuberances 38, 39 and of the plate 4.

Like the peripheral margins 32 of the plates 4, the protuberances 38, 39are terminated by a flat surface 46, which extends in a plane parallelto the bottom 43 of the protuberances 38, 39. The inlet protuberances 38and/or the outlet protuberances 39 of one and the same pair of plate arein contact with and brazed to one another at the level of an internalsurface of these flat surfaces 46.

The margins 32, 44, 60 are parallel to one other at the level of theprotuberances 38, 39. They are of flared shape in proximity to theprotuberances 38, 39, that is to say that they are of flared shape in azone lying, in particular, between 0 and 30 mm from the protuberances.This flaring of the margins 32, 44, 60 makes it possible to enlarge thecircuit 8 for the circulation of the coolant liquid in the event thatthe widening is present in proximity to the inlet protuberance 38, andto reduce the circuit 8 for the circulation of the coolant liquid in theevent that the widening is present in proximity to the outletprotuberance 39. The margins 32, 60 of the plates 4 are then parallel toone another as far as a zone in which a change takes place in thedirection of flow of the coolant liquid.

The circuit 8 defined by the plates 4 makes it possible to guide thecoolant liquid into a number n of successive passageways, in this casebeing two in number, in which the coolant liquid circulates from theinlet 40 towards the outlet 42. Two adjacent passageways are separated,for example, by the one or the plurality of central margins 60 of theplates 4. The passageways are arranged parallel to one another in anextension direction, in this case the large side of the plates 4. Theycan also be provided in series one after the other.

The circulation of the coolant liquid, changing its direction of flowfrom one passageway to the other, thus takes place in a direction thatis generally perpendicular to that of the flow of the fluid to be cooledpassing through the exchanger from the inlet surface of the array to itsoutlet surface, that is to say from one of the two large sides of theplates 4 to the other of the two large sides.

In the depicted example, where the plate 4 defines two passageways, theplate comprises a single central margin 60. It can also comprise halfmargins 60′, parallel to the central margin 60 and to the peripheralmargins 32, in such a way as to divide a single passageway into aplurality of sub-passageways. The central margin 60 is thus orientedtowards the large side of the plates 4 in order to define a serpentinecirculation of the coolant liquid in each of the passageways of each ofthe circuits 8 for the circulation of the coolant liquid. The centralmargin 60 extends, for example, from the left-hand lateral edge 16towards the right-hand lateral edge 17 of the plate, while leaving apassageway free to enable the coolant liquid to flow from the passagewaypresent on one side of the central margin 60 to the other passagewaypresent on the other side of the central margin 60.

The plate in this case comprises a number of baffles 55 situated insidethe circuits 8. These baffles 55 arise, for example, from the materialof the bottom of the plates 4, in particular by deep-drawing the plates.They may adopt a hemispherical shape, as illustrated in FIG. 2, or, forexample, a more elongated shape.

Once assembled, the plates 4 are grouped together in pairs and incontact at the level of their flat surfaces 34, 46 and/or their margins32, 60, 44. In this way, the circuit 8 of the upper plate and of thelower plate in one and the same pair of plates complement one another inorder to constitute a circulation channel for the coolant liquid. Theplates 4 are thus stacked by pairs, in such a way that the circuit 8 forthe circulation of the coolant liquid of one of the two plates issituated opposite the circuit 8 for the circulation of the coolantliquid of the other of the two plates in one and the same pair, in orderto form the circulation channel for coolant liquid.

In this way, the protuberances 38, 39 of the lower plate 4 of a pair ofplate are situated opposite a number of protuberances 38, 39 of theupper plate 4 of the same pair of plate.

Returning now to the heat exchanger depicted in FIG. 1, it will be notedthat the protuberances penetrate into the collector plate of theexchanger, in this case the left-hand wall 18 of the housing 5.

In order to cause the coolant liquid C to enter into and to exit fromthe circuits 8 of the various plates 4 of the exchanger 1, the lattercomprises an inlet collection box 71 and an outlet collection box 72 forthe coolant liquid C. The inlet collection box 71 is situated opposite anumber of inlet protuberances 38 of the plates 4 and, together with azone of the left-hand wall 18 at the level of which the inletprotuberances discharge, forms an inlet collector 73 for the coolantliquid C. In the same way, the outlet collection box 72 is situatedopposite a number of outlet protuberances of the plates 4 and, togetherwith a zone of the left-hand wall 18 at the level of which the outletprotuberances 39 discharge, forms an outlet collector 74 for the coolantliquid.

The collection boxes 71, 72 have the shape of a skirt that is open atthe level of the left-hand wall 18 of the housing 5 in order to permitthe coolant liquid C to enter into and/or to exit from the circuits 8for the circulation of the coolant liquid by means of the protuberances.The collecting boxes 71, 72 likewise exhibit an opening, not illustratedhere, in order to permit the coolant liquid C to enter into and/or toexit from the collectors 73, 74, that is to say to enter into and/or toexit from the exchanger 1.

The skirts in this case comprise two lateral surfaces 75, 76 situated toeither side of protuberances and one surface, referred to as theleft-hand surface 77, linking the two lateral surfaces 75, 76. It mustbe noted that lateral surfaces 75, 76 can exhibit forms that are flaredfrom a lower or upper edge of the boxes towards an opposite surface thatis provided with the inlet/outlet opening for the coolant fluid. Inother words, the section of the skirts in a plane parallel to the planein which the bottom of the plates 4 extends decreases from the uppersurface as far as the lower surface.

The boxes 71, 72 are secured to the collector plate 18 by a distalcontour, defined here by a folded edge 90 supported against saidcollector plate 18. Thanks to the flared form imparted to the circuit 8in proximity to the protuberances, the boxes can be configured in such away as to exhibit a width, that is to say a distance, between the twolateral surfaces 75, 76 of said boxes 71, 72, enabling the collectorplate to exhibit a width, that is to say a distance, between theinlet/outlet surfaces for the fluid to be cooled, which width issubstantially equal to, or slightly greater than, the length of thelateral edges of the plates 4.

The coolant liquid C thus penetrates into the exchanger 1 by enteringinto the inlet collector 73, for example by means of inlet/outlet tubes(not illustrated here). It is then distributed between the plates 4 inthe circuits 8 for the circulation of the coolant liquid by means of theinlet protuberances. It then flows by doubling back into the twopassageways of the circuits 8 for the circulation of the coolant liquidfrom the inlets into the outlets, at the level of which it exits fromthe array 2 before entering into the outlet collector 74. The coolantliquid C is then able to exit from the exchanger 1, for example via theinlet/outlet tubes.

FIG. 3 permits an aspect of the invention to be illustrated, accordingto which the left-hand wall 18 of the box 5, that is to say thecollector plate, comprises a plane section 80 and collars 81 surroundingthe protuberances 38, 39. Each collar 81 in this case comprises twoprotuberances 38, 39 in contact with one another and belonging to oneand the same pair of plate. Their roles is to facilitate the insertionof the protuberances 38, 39 into the collector plate, in order to ensuretheir mechanical support and to guarantee the sealing between the inletand/or outlet collectors and the array 2 for the exchange of heat forthe cooling liquid and the fluid to be cooled. The collars 81 areproduced by slotting the collector plate, for example, and are brazed tothe protuberances 38, 39, in particular in a manner that is simultaneouswith the brazing of the rest of the exchanger.

The collars 81 comprise an upper section 82 in contact with theprotuberance 38, 39 of an upper plate of a pair of plate and a lowersection 83 in contact with the protuberance 38, 39 of a lower plate ofthe same pair of plate. The lower and upper sections 82, 83 of thecollars 81 are mutually symmetrical in relation to a plane passingthrough the flat surfaces 46 of the protuberances 38, 39.

Contact between the collars 81 and the protuberances takes place inparticular at the level of the bottom 43 and the margins 44 of theprotuberances 38, 39. The collars 81 in fact conform to an externalsurface of the margins 44 of the protuberances 38, 39 and to an externalsurface of the bottom 43 of the protuberances 38, 39.

The flat surfaces 46 of the protuberances 38, 39 are terminated at thelevel of a lateral surface 84. These lateral surfaces 84 are not incontact with the collars 81. In fact, the upper section 82 and the lowersection 83 of the collars 81 are terminated at the level of the externalsurfaces of the flat surfaces 46 of the protuberances 38, 39 and do notsurround the lateral surfaces of the flat surfaces 46. These lateralsurfaces are thus directly in contact with the plane section 80 thecollector plate.

FIG. 4 permits the illustration of the baffles 52 for the flow of thefluid to be cooled, which baffles extend between two adjacent pairs ofplates. Thanks to the invention, these baffles 52 extend from onelateral wall of the box to the other. The left-hand lateral wall 18 inthis case plays the role of a collector plate for the coolant liquid,and the baffles 52 are situated in proximity to the collector plate,that is to say at less than 1 mm from the collector plate. The exchangeof heat is accordingly optimized, since it takes place in a zoneextending from the left-hand lateral wall 18 of the box to theright-hand lateral wall of the box.

The different component parts of the exchanger are made of aluminum oran alloy of aluminum, for example. In particular, they are brazed to oneanother.

1. A plate for exchanging heat between a first and a second fluidcirculating in contact with the plate, the plate configured to define acircuit for the first fluid, wherein the plate comprises one or aplurality of protuberances penetrating into a collector plate for thefirst fluid and defining an inlet into and/or an outlet from thecircuit.
 2. The plate as claimed in claim 1, comprising twoprotuberances respectively defining the inlet into and the outlet fromthe circuit.
 3. The plate as claimed in claim 1, comprising two smallsides and two large sides, such that the plate possesses the shape of arectangle, the one or the plurality of protuberances being situated at alevel of the small sides of the rectangle.
 4. The plate as claimed inclaim 1, wherein the plate and the one or the plurality of protuberancescomprise a bottom and margins defining the circuit, the bottom of theone or the plurality of protuberances and the bottom of the plateextending in a plane.
 5. The plate as claimed in claim 4, in which themargins delimiting the circuit are parallel to one another at the levelof the one or the plurality of protuberances and the margins are flaredout in a direction of the circuit (8).
 6. An array for exchanging heat,the array comprising a stack of plates according to claim 1, the platesbeing arranged in pairs such that two plates of the same pair define acirculation channel for the first fluid.
 7. A heat exchanger comprisingthe array for exchanging heat as claimed in claim 6 and the collectorplate, penetrated by the one or the plurality of protuberances of theplates.
 8. The heat exchanger as claimed in claim 7, comprising ahousing provided with four walls and having an interior with the arraydisposed within the interior, and with the collector plate furtherdefined as one of the four walls.
 9. The heat exchanger as claimed inclaim 7, comprising at least one inlet collector, into an interior ofwhich the one or the plurality of protuberances of the plates definingthe inlet into the circuits discharge, and one outlet collector, into aninterior of which the one or the plurality of protuberances of theplates defining the outlet from the circuits discharge.
 10. The heatexchanger as claimed in claim 7, in which the collector plate comprisesa plane section and collars surrounding the one or the plurality ofprotuberances.
 11. The heat exchanger as claimed in claim 10, whereinthe one or the plurality of protuberances comprise margins terminatingat a flat surface permitting brazing of the one or the plurality ofprotuberances to one another and the margins extending in a planeparallel to a plane in which the bottom of the one or the plurality ofprotuberances extends.
 12. The heat exchanger as claimed in claim 11, inwhich two plates forming a pair of plates are in contact at a level ofan internal surface of the flat surfaces.
 13. The heat exchanger asclaimed in claim 11, wherein the collars conform to an external surfaceof the margins of the one or the plurality of protuberances and anexternal surface of the bottom of the one or the plurality ofprotuberances and/or a lateral surface of the flat surfaces is incontact with the plane section of the collector plate.
 14. The heatexchanger as claimed in claim 7, comprising baffles disposed therein,the baffles extending between two pairs of plates until the baffles arein proximity to the collector plate.
 15. A module for admission of aircomprising an exchanger according to claim 7.